HALLAHAN, MARGARET. - Dominican Tertiary nun, born in London to Irish parents on 23 January 1802; died 11 May 1868. Orphaned at ages nine and ten by the deaths of her father and mother, she immediately entered a long period of domestic service, first in England (1813–26) and then in Bruges, Belgium (1826–42). Returning to England in 1842, she matured the idea of becoming a Dominican and founding a congregation of sisters, finding support for this in the Benedictine Fr. Ullathorne, later Bishop of Birmingham.
In 1844, the English Congregation of St. Catherine of Siena began in Coventry, with Hallahan playing a central role. She also devoted herself to various educational and charitable institutions, leaving at her death numerous foundations: five convents, four churches, schools, houses, and orphanages, so meriting the title “mother of all.” She is also regarded as one of the principal instruments of Providence for the restoration of Catholicism and its chief devotions in England during the last century. For several years, processes for her beatification have been underway.